Composition

ABSTRACT

A composition that is useful in a skin function improving agent includes at least a sapogenol, and a collagen hydrolysate. This composition can be used in a skin function improving agent and is particularly useful in a skin function improving agent for inhibiting transdermal moisture loss and/or for retaining the moisture in the stratum corneum.

TECHNICAL FIELD

The present invention relates to a novel composition containing at leasttwo of vitamin K, sapogenol, and collagen hydrolysate, and moreparticularly relates to the composition that is useful as a skinfunction improving agent.

BACKGROUND

The skin is mainly divided into the epidermis, dermis, and subcutaneoustissue. The epidermis is further divided into, from the surface, thesebaceous membrane, stratum corneum, stratum granulosum, stratumspinosum, and stratum basale.

The sebaceous membrane consists of the sebum secreted from the sebaceousgland, the sweat gland, or the like. Sebum plays a role in preventingwater loss. Transepidermal water loss (TEWL) means the amount of waterthat is volatilized unconsciously from the body through the stratumcorneum. The amount of sebum and TEWL are inversely correlated; forexample, if the amount of sebum is large, TEWL is decreased. A higherTEWL value means decreased barrier function of the stratum corneum. As aresult, the skin becomes grainy or dry, resulting in rough skin. Ifsecretion of sebum is too much, the skin becomes oily and sticky and thesebum is changed to an irritant, which is a factor for inflammation andacne of the skin. Moderate secretion of sebum is needed so that thesebaceous membrane can perform an important function.

In the stratum corneum under the sebaceous membrane, corneocytes filledwith hard keratin proteins are stacked in about 1 mm layers. Eachcorneocyte is linked by intercellular lipids. The structure of thestratum corneum is so compact that water and fluid in the body do notleak out. The phenomenon that basal cells divide once when corneocytesin the top layer of the stratum corneum is shed is referred to askeratinization. As a result of the fact that old keratin is shed to bereplaced by a new corneocyte, the functions of the stratum corneum aremaintained and the thickness of the epidermis is kept constant.

Even when corneocytes are formed by hard keratin proteins, softness ofthe skin needs to be maintained to some extent. To do this, the stratumcorneum contains 20% to 30% of moisture. If moisture is lost, keratinbecomes hard and the skin becomes dry.

Natural moisturizing factor (NFM) plays a role in retaining the moisturein the stratum corneum. NFM consists of amino acid, PCA (pyrrolidonecarboxylic acid), lactate, urea, and the like. NMF having highhydrophilicity is helpful in retaining moisture.

Intercellular lipids are lipids formed by keratinization ofkeratinocytes. Intercellular lipids consist of ceramides, cholesterol,cholesteryl ester, and the like. Ceramide and free fatty acids such aslinoleic acid contained therein play a role in retaining moisture andthe barrier function of the stratum corneum. If an abnormality occurs inintercellular lipids, the water-retaining function is lost, the skinbecomes dry, and inflammation becomes likely to occur.

The dermis is positioned under the stratum basale of the epidermis, andis a layer with a thickness of 2 mm consisting of protein fibers thatare constituted of collagen and elastin and substrates. Collagen plays arole in providing taut skin and supporting elastin. Elastin provideselasticity to the skin even though by about 2%. Substrates filling thespace between protein fibers are extracellular matrix components such asproteoglycan and hyaluronic acid. Intercellular lipids retain most ofthe moisture in the dermis. In the skin with youthfulness maintained,production of extracellular matrix components is promoted, and theelasticity, water retention, and tautness of the skin are kept.

Internal factors such as aging, disease, stress, and hormoneabnormalities and external factors such as dryness and ultraviolet raysdecrease moisture and extracellular matrix (e.g., collagen, hyaluronicacid) from dermal tissues and decrease the functions of the epidermisand dermis of the skin. Decreased skin functions appear as skinwrinkles, decreased elasticity (slackness), or rough skin.

To solve problems regarding beauty including skin aging and rough skin,functional foods for ingestion of various active ingredients andcosmetic compositions have been developed and marketed.

JP 2008-99562 A (Skin-Beautifying Oral Composition) discloses askin-beautifying oral composition containing royal jelly, isoflavone,and collagen. This disclosure provides food having skin-beautifyingeffect of improving softness of the skin and fixing up skin texture.

JP 2000-93121 A (Beauty Food) discloses beauty food containing at leastone of kuma bamboo grass (Sasa albo-marginata), five-leaf ginseng(Gynostemma pentaphyllum), Siberian ginseng (Acanthopanax senticosusHarms), betaine, and soyasaponin, and a collagen peptide. Thisdisclosure provides a beauty food enabling the restoration of skintension and gloss and the maintenance of a moist and young bare skin.

JP 11-35445 A (Cosmetic Composition) discloses a cosmetic compositionobtained by combining soyasaponin with at least one of hyaluronic acid,salt of hyaluronic acid, collagen, and elastin. This disclosure canenhance skin brightness and maintain healthy and beautiful skin by thesynergy of the effect of preventing skin aging by inhibiting theproduction of subcutaneous lipid peroxide by the combination ofsoyasaponin with the moisture retention effect by the combination of atleast one of hyaluronic acid, salt of hyaluronic acid, collagen, andelastin.

JP 10-29911 A (Cosmetic Material Composition) discloses a cosmeticmaterial composition containing an extract of soybean and adzuki beanpowder as essential active ingredients. This disclosure describes areduction of the abnormality of the skin with increased lipid peroxidein the body, i.e., somber and stained skins, rough skin, and the like.

JP 2004-250372 A (Skin Aging Inhibitor/Improver and/or Rough SkinInhibitor/Improver Kit) discloses a drink containing an activeingredient effective for beautifying skin and alcohol, and a skin aginginhibitor/improver and/or rough skin inhibitor/improver kit includingthe drink and a soybean germ extract-containing external preparation.The active ingredient effective for beautifying skin is selected frombiological collagen synthesis promoter, abnormal protein remover, femalehormone-like agent, and moisturizer.

SUMMARY

It is an object of the present invention to provide a novel compositionthat is highly effective in improving the skin function.

By diligently considering the above problem, the present inventors havesuccessfully increased the effect on the skin improving function by thecombination of at least two specified components compared with thesingle use, and completed the present invention.

In other words, the present invention provides a composition containingat least two components selected from the group consisting of vitamin K,sapogenol, and collagen hydrolysate.

The prior art mentions a composition containing saponin or collagenhydrolysate, but does not mention a composition containing at least twocomponents selected from the group consisting of vitamin K, sapogenol,and collagen hydrolysate, like the present application invention. Thefact that combination of at least two components has synergistic effectson the skin improving function is also not known at all.

A composition of the present invention preferably essentially containsthe vitamin K.

The vitamin K is preferably vitamin K2.

The vitamin K2 is particularly preferably menaquinone-7.

The sapogenol is, for example, derived from soybean.

In the collagen hydrolysate, the content of peptide having a molecularweight from 200 to less than 3,000 is preferably not less than 40% bymass.

The present invention also provides a skin function improving agent withthe active ingredient of the above composition.

The skin function improving agent contains the vitamin K and thesapogenol, and is for inhibiting transdermal moisture loss.

The skin function improving agent contains the vitamin K and thecollagen hydrolysate, and is for retaining the moisture in the stratumcomeum.

As mentioned above, decreases in water retained on each layer of dermaltissues are associated with decreased skin functions. According to thepresent invention that essentially contains at least two componentsselected from the group consisting of vitamin K, sapogenol, and collagenhydrolysate, synergistic effects that cannot be achieved by a singlecomponent regarding the water retention in dermal tissues can beobtained, although the reason is not clear.

A composition of the present invention has a skin function improvingfunction. Therefore, the composition of the present invention is usefulas a skin function improving agent. The skin function improving agent isprovided as functional foods, supplements, pharmaceuticals, and/orcosmetics.

When the skin function agent contains the vitamin K and the sapogenol,effects of inhibiting the transdermal moisture loss are exerted. Whenthe skin function agent contains the vitamin K and the collagenhydrolysate, effects of retaining the moisture in the stratum corneumare exerted.

Since the above mentioned three components are derived from naturalplants and animals, it is likely that they have few side effects.Long-term intake or application of the composition of the presentinvention can provide excellent effects.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1A is a view showing effects when the composition of the presentinvention was used as a skin function improving agent. The view showsthe skin moisture loss amount fluctuation values (difference in theamount on day 28 after administration to the day before test substanceadministration) in Example 1 (menaquinone-7+collagen hydrolysate),Comparative Example 1 (menaquinone-7), and Comparative Example 2(collagen hydrolysate). Comparison of Example 1 with Comparative Example1 and Comparative Example 2 reveals that the combination ofmenaquinone-7+collagen hydrolysate exerts the synergistic effects oninhibiting the skin moisture loss.

FIG. 1B is a view showing the skin moisture loss amount fluctuationvalues, like FIG. 1A. Example 2 (menaquinone-7+soyasapogenol) exertsmore marked synergistic effects on inhibiting the skin moisture loss,compared with Comparative Example 1 (menaquinone-7) and ComparativeExample 3 (soyasapogenol).

FIG. 1C is a view showing the skin moisture loss amount fluctuationvalues, like FIG. 1A. Example 3 (collagen hydrolysate+soyasapogenol)exerts more synergistic effects on inhibiting the skin moisture loss,compared with Comparative Example 2 (collagen hydrolysate) andComparative Example 3 (soyasapogenol).

FIG. 2A is a view showing effects when the composition of the presentinvention is used as a skin function improving agent. The view shows thekeratin moisture fluctuation values (difference in the moisture on day28 after administration to the day before test substance administration)in Example 1 (menaquinone-7+collagen hydrolysate), Comparative Example 1(menaquinone-7), and Comparative Example 2 (collagen hydrolysate).Comparison of Example 1 with Comparative Example 1 and ComparativeExample 2 reveals that the use of menaquinone-7 or collagen hydrolysatealone has no function of keratin water retention (moisture retention),while the combination of menaquinone-7+collagen hydrolysate has suchfunction.

FIG. 2B is a view showing changes in the keratin moisture, like FIG. 2A.Comparison of Example 2 (menaquinone-7+soyasapogenol) with ComparativeExample 1 (menaquinone-7) and Comparative Example 3 (soyasapogenol)reveals that menaquinone-7 has no stratum corneum water-retainingfunction, while the combination of soyasapogenol and menaquinone-7exerts a keratin water-retaining function similar to that bysoyasapogenol.

FIG. 2C is a view showing changes in the keratin moisture, like FIG. 2A.Comparison of Example 3 (collagen hydrolysate+soyasapogenol) withComparative Example 2 (collagen hydrolysate) and Comparative Example 3(soyasapogenol) reveals that collagen hydrolysate has no stratum corneumwater-retaining function, while the combination of soyasapogenol andcollagen hydrolysate exerts a keratin water-retaining function.

DETAILED DESCRIPTION

One embodiment of the composition of the present invention will bedescribed in detail below. Vitamin K that can be used for thecomposition of the present invention includes vitamin K1 to K3. VitaminK1 (also referred to as phylloquinone) is abundantly contained in greenand yellow vegetables, pulse, vegetable oil, seaweed, seafood, and thelike. Vitamin K2 (also referred to as menaquinone) is produced bymicroorganisms, and is abundantly contained in fermented soybeans anddairy products such as cheese. Vitamin K2 is also produced by intestinalbacteria. Depending on the length of a side-chain isoprenoid groupattached to the naphthoquinone skeleton, homologs of vitamin K2 frommenaquinone-4 (MK-4) to menaquinone-15 (MK-15) exist. For example, MK-6to MK-9 are abundantly contained in cheese and MK-7 is abundantlycontained in fermented soybeans. Vitamin K3 (also referred to asmenadione) is a complex.

There is no particular limitation on the manufacturing method of eachvitamin K. Commercial vitamin K can also be used without limitation.

Vitamin K1 is extracted and purified by publicly known methods (forexample, JP 5-155803 A) from green perilla, perilla (Perillafrutescens), Jew's marrow, parsley, garland chrysanthemum, Komatsuna(Brassica rapa var perviridis), spinach, Japanese honewort, alfalfa,leaf of Asian Hazel, leaf of chestnut, spear of barley, spear of wildoat, cabbage, broccoli, cauliflower, tomato, vegetable oil (soybean oil,rapeseed oil, sesame oil, peanut oil, corn oil, safflower oil, sunfloweroil, rice bran oil, and olive oil), and the like. Vitamin K1 can also beobtained from synthesis. Vitamin K1 is fat-soluble, pale yellow, oily,and stable for heat, but unstable for light. Vitamin K1 may be an oxide.

Vitamin K2 is fermented and produced by microorganisms such as Haybacillus (Bacillus subtilis var. natto) in accordance with, for example,methods mentioned in JP 08-073396 A, JP 11-92414 A, JP 10-295393 A, JP2001-136959 A, and the like.

Vitamin K3 can be obtained by chemosynthesis.

Intake of large amount of vitamin K3 raises a concern of side effects.Therefore, from our previous eating experience, vitamin K1 that isextracted and purified from vegetables and vitamin K2 that is extractedfrom fermented products using Hay bacillus (Bacillus subtilis var.natto) and the like are preferable in terms of higher safety. Vitamin K2that can be produced inexpensively and easily is more preferable.Menaquinone-4 that is approved as a food additive and/or menaquinone-7that is utilized as a food material are particularly preferable.

The content of vitamin K in the composition of the present inventionvaries depending on the use or form of the composition, but may beusually 0.00001 to 99% by weight, preferably 0.00005% to 70% by weight,more preferably 0.0001 to 60% by weight, and still more preferably 0.01to 50% by weight. If the content of vitamin K is 0.00001% by weight orless, synergistic effects by using in combination with other components(collagen hydrolysate and/or sapogenol) may not be obtained.

Saponin is an amorphous glycoside which is abundantly present insoybeans, adzuki beans, olive, and the like. Saponin is named since ithas a hydrophobic portion and a hydrophilic portion and forms persistentbubbles when mixed with water and shaken. Saponin is broadly classifiedinto steroid saponin and triterpenoid saponin according to the type ofaglycone. The soyasaponin contained abundantly in soybeans, particularlyin a soybean hypocotyl is a kind of the triterpenoid saponin. Sapogenolmeans the aglycone in which the part or whole of sugar chain residuesare removed from the saponin glycoside derived from soybeans, adzukibeans, or olive. Sapogenol used for the composition of the presentinvention is preferably derived from soybeans.

Soyasapogenol derived from soybeans includes soyasapogenol A, which canbe obtained from soyasaponin Aa, Ab, Ac, Ad, Ae, Af, Ag, and Ah(soyasaponin A group glycoside), and soyasapogenol B, which can beobtained from soyasaponin I, II, III, IV, and V (soyasaponin B groupglycoside).

Soyasapogenol can be obtained by removing the part or whole of sugarchains from soyasaponin glycoside. Specifically, soyasaponin glycosideis subjected to enzymatic reaction with glycosidase (US 2006/0275862),high temperature and pressure treatment (WO 2008/155890), orfermentation treatment. Soyasapogenol may be obtained by chemosynthesis(JP 2005-137201 A). The above mentioned literatures will be insertedinto the present description for reference.

Soyasapogenol having part of sugar chain residues (e.g.,3-O-D-glucuronopyranosyl soyasapogenol B, 3-O-D-glucuronopyranosylsoyasapogenol A) can be obtained by partial acid decomposition ofsoyasaponin glycoside. Specifically, after dissolving the soyasaponinglycoside into an organic solvent such as ethanol, methanol, andbutanol, an acid such as sulfuric acid and hydrochloric acid is added.As another method, soyasaponin glycoside is added to and dissolved intoa reaction solvent obtained by diluting the acid with water, ethanol,methanol, or the like. The acid decomposition is started by heating thesolution to which the acid is added. An acid decomposition temperatureis appropriately selected based on the type and concentration of theacid, a degree of the partial decomposition, and the like. A degree ofprogress of the partial decomposition is detected by using anappropriate detector (e.g., chromatography), and when the predetermineddegree of decomposition is achieved, the solution is neutralized using abase such as sodium hydroxide. The solid phase is collected bysubjecting the neutralized product to centrifugation, filtration, or thelike. Apart from the desired soyasapogenol, the collected product cansometimes contain conventional soyasapogenol, raw material glycoside,protein, oligosaccharide, and the like as impurities, and thus anappropriate purification (e.g., column chromatography) may be performedto purify objects.

Soyasaponin glycoside itself can be extracted from the cotyledon, germ,or whole grains of soybeans by publicly known methods. Specifically,soyasaponin glycoside is extracted and purified from the cotyledon,germ, or whole grains of soybeans by the method mentioned in JP 03-75939X, and the like. Commercial soyasaponin glycoside can be used withoutparticular limitation.

The content of sapogenol in the composition of the present inventionvaries depending on the use or form of the composition, but may beusually 0.00002 to 99% by weight, preferably 0.0001% to 70% by weight,more preferably 0.005 to 60% by weight, and still more preferably 0.01to 50% by weight. If the content of sapogenol is 0.00002% by weight orless, synergistic effects by using in combination with other components(vitamin K and/or collagen hydrolysate) may not be obtained.

Collagen is a fibrous protein having a molecular weight of about 300,000having strong rigidity like steel. Collagen is abundantly contained inthe dermis of the skin, tendon, artery, cartilage, and the like ofanimals such as mammal, bird, and fishes. Collagen can be extracted bywashing the dermis of the above mentioned animals and subjecting it toan alkali treatment and neutralization.

Collagen hydrolysate can be obtained by degenerating collagen by heat tomake gelatin and further hydrolyzing gelatin so that the molecularweight is as small as thousands to hundreds. For hydrolysis reaction,usually proteases such as trypsin, chymotrypsin, and subtilisin areused. The reaction conditions such as reaction temperature, reactiontime, and pH are appropriately adjusted depending on enzymes used oramount. After the end of hydrolysis, heating to inactivate enzymes andcooling are carried out, and then filtration and drying are performedappropriately. A commercial product of collagen hydrolysate (e.g.,product name: collagen tripeptide, JELLICE Co., Ltd.) can be used.

Collagen hydrolysate usually becomes a peptide mixture having amolecular weight distribution of 100 to 10,000. The content oftripeptide having a molecular weight of 200 to 1,000 is usually 5 to 30%by mass.

In collagen hydrolysate used for the present invention, the content ofpeptide having a molecular weight from 200 to less than 3,000 ispreferably not less than 40% by mass, more preferably not less than 50%by mass, and still more preferably not less than 60% by mass.

The content of collagen hydrolysate in the composition of the presentinvention varies depending on the use or form of the composition, butmay be usually from 0.00003 to 99% by weight, preferably from 0.0003% to95% by weight, more preferably from 0.003 to 90% by weight, and stillmore preferably from 0.03 to 85% by weight. If the content of collagenhydrolysate is not more than 0.00003% by weight, synergistic effects byusing in combination with other components (vitamin K and/or sapogenol)may not be obtained.

The composition of the present invention exerts a function of inhibitingthe moisture loss from the sebaceous membrane (skin barrier function) asseen in FIG. 1A to 1C by containing at least two of the above mentionedessential three components. As seen in FIGS. 1A and 1B, essentiallycontaining vitamin K2 is preferable in terms of improvement in the skinbarrier function. As seen in FIG. 1B, essentially containing vitamin K2and soyasapogenol is preferable in terms of further improvement in theskin barrier function.

The composition of the present invention exerts a function of retainingthe moisture in the stratum corneum (moisture-retaining function) asseen in FIGS. 2A to 2C by containing at least two of the above mentionedessential three components. As seen in FIG. 2A, the use of vitamin K orcollagen hydrolysate alone does not exert the moisture-retainingfunction, while the combination of vitamin K and collagen hydrolysateexerts the moisture-retaining function.

The composition of the present invention is manufactured byappropriately combining aids or accessory components publicly known inthe fields of functional foods, supplements, pharmaceuticals, andcosmetics.

The composition of the present invention can be expected to have atransdermal moisture loss-inhibiting function and a function ofretaining the moisture in the stratum corneum. The composition of thepresent invention is provided as a functional food or supplement thatretains skin moisture and improves the status of the skin such as skinwrinkles, slackness, and rough skin based on the moisture retention.

Orally taking the composition of the present invention exertsbeautifying effects intended for retaining skin moisture and improvingrough skin. These effects are functions of cosmetics intended forbeautifying, and therefore, the composition of the present invention canbe said as orally taken cosmetics.

When the composition of the present invention is used as a functionalfood or supplement that improves skin functions, in addition to theessential components, materials used for general purpose as additives ofsupplements may be added. For example, depending on the form of theorally-administered agent, diluent for general-purpose use;disintegrant; binder; lubricant; pH adjuster; cooling agent; suspendingagent; emulsifier; viscous agent; solubilizer; antioxidant; coatingagent; plasticizer; surfactant; corrigent; edulcorant; acidulant and thelike such as citric acid; water; flavor; coloring agent; vitamins suchas vitamin A, biotin, vitamin B1, vitamin B2, vitamin B6, vitamin B12,vitamin C, vitamin D, vitamin E, vitamin P, folic acid, inositol,pantothenic acid, and niacin; minerals such as calcium, potassium,sodium, phosphorus, sulfur, iron, and zinc; xanthine derivative;protein; amino acids such as glycine, alanine, proline, arginine, andglucosamine; plant extract such as rose extract; fatty acids such asoleic acid, linoleic acid, α-linolenic acid, γ-linolenic acid,arachidonic acid, eicosapentaenoic acid, docosahexaenoic acid, andcholesterol; fatty alcohol; water-soluble polymer; saccharides such asoligosaccharide, fructose, and lactose; dietary fibers such as insolubledietary fiber, water-soluble dietary fiber, chitin, and chitosan;ceramide; glucosamine; N-acetylglucosamine; hyaluronic acid; chondroitinsulfate; polyphenol; coenzyme Q10, and the like can be added in thequalitative and quantitative range that does not impair the advantageouseffects of the invention.

To use the composition of the present invention as a functional food orsupplement, it is processed into an orally-administered agent such as,dusting powder, powder, granule, capsule, pill, tablet, chewable tablet,drop, biscuit, jelly, gel, syrup, and solution. Since sapogenol ispowder, the form of tablet is desirable.

For the intake of the composition of the present invention when used asa functional food or supplement, the intake of vitamin K per day ispreferably 0.01 to 50 mg, more preferably 0.01 to 1 mg, by consideringsymptoms and safety. The intake of sapogenol per day is preferably 0.1to 100 mg, and more preferably 5 to 50 mg. The intake of collagenhydrolysate per day is preferably 0.1 to 15 g, and more preferably 1 to10 g.

The composition of the present invention may be directly added to rawmaterials when general processed food such as bread, rice, soup, sidedish, confectionery, and candy is processed.

When the composition of the present invention is used as apharmaceutical that improves skin functions, in addition to theessential components, materials used for general purpose as aids topharmaceuticals may be added. For example, depending on the dosage formand administration method, diluent for general-purpose use,disintegrant, binder, lubricant, vitamin, xanthine derivative, aminoacid, pH adjuster, cooling agent, suspending agent, viscous agent,solubilizer, antioxidant, coating agent, plasticizer, surfactant, water,alcohol, water-soluble polymer, edulcorant, corrigent, acidulant,flavor, coloring agent, and the like can be added in the qualitative andquantitative range that does not impair the advantageous effects of theinvention.

To use the composition of the present invention as a pharmaceutical, itis processed into the forms of orally-administered agents such as solidpreparation like solution, powder, granule, capsule, pill, tablet,chewable tablet, and drop and such as solution like drinkablepreparation, pharmaceutical solution, suspension, emulsion, syrup, anddry syrup, or of transdermally-administered agents like pharmaceuticalsolution, emulsion, and cream. Since sapogenol is powder, the form ofsolid preparation is desirable.

There is no particular limitation on the intake method when thecomposition of the present invention is used as a pharmaceutical. Forexample, the method includes oral intake, transdermal intake, and thelike. In terms of less burden on patients, oral intake of tablets,capsules, and the like is preferable.

When the composition of the present invention is used as apharmaceutical, the intake may be established appropriately depending onsymptoms, but generally, when it is used as a preventive, the intake ofmenaquinone-7 per day may be usually 10 μg to 100 mg, preferably 20 μgto 100 mg, and more preferably 5 to 50 mg. When it is used as atherapeutic agent, it can be used with the intake of 1 to 150 mg.

When the composition of the present invention is used as apharmaceutical, the intake may be established appropriately depending onsymptoms, but generally, when it is used as a preventive, the intake ofsapogenol per day is preferably 0.1 to 100 mg, and more preferably 5 to50 mg. When it is used as a therapeutic agent, the intake is preferably5 to 1,200 mg, and more preferably 150 to 900 mg.

When the composition of the present invention is used as apharmaceutical, the intake may be established appropriately depending onsymptoms, but generally, when it is used as a preventive, the intake ofcollagen hydrolysate per day is preferably 0.1 to 15 g, and morepreferably 1 to 10 g. When it is used as a therapeutic agent, the intakeis preferably 0.1 to 20 g, and more preferably 1 to 15 g.

When the composition of the present invention is used as a cosmeticmaterial, apart from the essential components, materials used forgeneral purpose as aids to cosmetics may be added. They include, forexample, polyhydric alcohol such as ethylene glycol, polyethyleneglycol, propylene glycol, 1,3-butylene glycol, 1,4-butylene glycol,dipropylene glycol, glycerin, diglycerine, polyglycerin, pentyleneglycol, isoprene glycol, glucose, maltose, fructose, xylitol, sorbitol,maltotriose, and erythritol; lower alcohol such as methanol, ethanol,propyl alcohol, isopropyl alcohol, butyl alcohol, and isobutyl alcohol;higher fatty acids such as oleic acid, isostearic acid, lauric acid,myristic acid, palmitic acid, stearic acid, behenic acid, andundecylenic acid; fats and oils, such as olive oil, corn oil, camelliaoil, macadamia nut oil, avocado oil, rapeseed oil, sesame oil, castoroil, safflower oil, cottonseed oil, jojoba oil, coconut oil, and palmoil; waxes such as carnauba wax, candelilla wax, bees wax, and lanolin;saccharides such as sorbitol, mannitol, glucose, sucrose, lactose, andtrehalose; thickeners such as carrageenan, xanthan gum, gelatin, pectin,agarose, alginate, dextrin, methylcellulose, ethylcellulose,hydroxypropyl cellulose, hydroxyethyl cellulose, carboxymethylcellulose, carboxyvinyl polymer, polyvinyl alcohol,polyvinylpyrrolidone, gum arabic, karaya gum, Tragacanth gum, andtamarind gum; preservatives such as phenoxyethanol, methylparaben,ethylparaben, propylparaben, butylparaben, para-hydroxybenzoate, benzoicacid, salicylic acid and salts thereof, sorbic acid and salts thereof,dehydroacetic acid and salts thereof, chlorocresol, and hexachlorophene;nonionic surfactants such as sodium lauroyl sulfate and polyoxyethylenesorbitan monooleate, anionic surfactants such as alkyl sulfate salt andnormal dodecyl sodium benzenesulfonate, and cationic surfactants such aspolyoxyethylene dodecylmonomethylammonium chloride; steroidal andnonsteroidal antiinflammatory agents; vitamins such as vitamin A,vitamin D, vitamin E, vitamin F, and vitamin K and vitamin derivativessuch as pyridoxine dicaprylate, pyridoxine dipalmitate, ascorbyldipalmitate, ascorbyl monopalmitate, and ascorbyl monostearate;antioxidants such as flavonoid and carotenoid; higher aliphatichydrocarbons such as squalane, squalene, and liquid paraffin;sphingolipids such as ceramide, cerebroside, and sphingomyelin; sterolssuch as cholesterol and phytosterol; silicones such as methylpolysiloxane, methylphenylpolysiloxane, methylcyclopolysiloxane,octamethyl cyclotetrasiloxane, octamethyl cyclopentasiloxane, decamethylcyclopentasiloxane, and methyl hydrogen polysiloxane; ultravioletabsorbing agents such as para-aminobenzoic acid, para-aminobenzoic acidmonoglyceryl ester, methyl anthranilate, homomenthyl-N-acetylanthranilate, octyl para-methoxycinnamate, and ethyl-4-isopropylcinnamate; minerals such as bentonite, smectite, beidellite, nontronite,saponite, hectorite, sauconite, and stevensite; inorganic pigments suchas red iron oxide, yellow iron oxide, black iron oxide, cobalt oxide,ultramarine blue, iron blue, titanium oxide, and zinc oxide; coloringagents such as Red No. 202, Yellow No. 4, and Blue No. 404; flavor; andbalm.

To use the composition of the present invention as a cosmetic, it isprocessed into the forms of percutaneously administered agents such assolution, pharmaceutical solution, emulsion, milky liquid, cream, andpowder; or of orally administered agents, for example, solidpreparations such as powder, granule, capsule, pill, tablet, chewabletablet, and drop, and liquid preparations such as drink, pharmaceuticalsolution, suspension, emulsion, syrup, and dry syrup.

The intake method when the composition of the present invention is usedas a cosmetic is oral intake or transdermal intake. Transdermaladministration of pharmaceutical solution, emulsion, milky liquid, orcream is preferable in terms of immediate effects as a cosmetic.

For the intake when the composition of the present invention is used asa cosmetic material, the intake of vitamin K per day is preferably 0.01to 50 mg, and more preferably 0.01 to 1 mg, by considering symptoms andsafety. The intake of sapogenol per day is preferably 0.001 to 100 mg,and more preferably 0.05 to 50 mg. The intake of collagen hydrolysateper day is preferably 0.001 to 20 g, and more preferably 0.01 to 10 g.

Formulation Examples of the present invention will be shown below.However, the present invention is not limited to the followingFormulation Examples.

Formulation Example 1 Tablets

TABLE 1 Additive amount Composition (parts by weight) Cornstarch 40Crystalline cellulose 20 Carboxymethyl cellulose 10 Menaquinone-7 0.01Sapogenol 0.1 Collagen hydrolysate 10 Lactose Balance Total 100

Formulation Example 2 Capsules

TABLE 2 Additive amount Composition (parts by weight) Olive oil 80Beeswax 2 Glycerin 2 Menaquinone-7 0.01 Sapogenol 0.1 Collagenhydrolysate 10 Lactose Balance Total 100

Formulation Example 3 Lotions

TABLE 3 Additive amount Composition (parts by weight) Ethanol 10Glycerin 3 Propylene glycol 3 Menaquinone-7 0.001 Sapogenol 0.05Collagen hydrolysate 3 Flavor and preservative q.s. Purified waterBalance Total 100

Formulation Example 4 Creams

TABLE 4 Composition Additive amount (parts by weight) Squalane 10Glycerin 10 Liquid paraffin 5 Cetanol 3 Stearic acid 2 Lanolin 2Menaquinone-7 0.5 Sapogenol 0.05 Collagen hydrolysate 5 Flavor andpreservative q.s. Purified water Balance Total 100

EXAMPLES

The present invention will be described in more detail below by wayExamples, but the present invention is not limited to the followingExamples.

Example 1 1. Preparation of Composition (Skin Function Improving Agent)

Menaquinone-7, collagen hydrolysate, and soyasapogenol were prepared.For menaquinone-7, after a commercial menaquinone-7 reagent(manufactured by Wako Pure Chemical Industries, Ltd.) was subjected to apurity test with HPLC, menaquinone-7 with purity of 99.6% was used.

For collagen hydrolysate, a commercial collagen hydrolysate (productname: collagen tripeptide, manufactured by JELLICE Co., Ltd.) was used.The molecular weight distribution of the collagen hydrolysate is shownin Table 5.

TABLE 5 Molecular weight range Proportion (%) not less than 6,000 3 from3,000 to less than 6,000 15 from 1,000 to less than 3,000 48 from 500 toless than 1,000 12 from 200 to less than 500 8 less than 200 14 Total100

The content of tripeptide (molecular weight of 200 to 1,000) was 20%.

For soyasapogenol, a commercial soyasaponin preparation (product name:saponin B-50, manufactured by J-OILMILLS, Inc.) was used. This productcontained 27.4% of the saponin A group and 52.3% of the saponin B group.To 750 g of this product, 7.5 L of 80% ethanol containing 2N sulfuricacid was added, and the mixture was incubated at 75° C. for 25 hours.After incubation, 7.5 L of water was added to the reaction mixture tocentrifuge. Into the residue after centrifugation, 7.5 L of water wasadded to neutralize with 1N KOH. Further centrifugation was performed,further water was added from above of the centrifuge, and the mixturewas dried to obtain a powder of 251.5 g.

The soyasapogenol concentration in the powder was measured based on themethod by Rupasinghe et al. (J. Agric. Food. Chem. 51. 5888-5894, 2003).The results showed that 19.6% for soyasapogenol A and 45.8% forsoyasapogenol B.

In addition to the reference diet, the test substances shown in Table 6were administered to the study groups in Examples and ComparativeExamples. By dissolving the test substances in a 0.5% carboxymethylcellulose sodium solution (hereinafter referred to as CMC-Na solution),the composition (skin function improving agent) was prepared.

The amount of combination of the test substances and the composition wasprepared so that the dose of the 0.5% CMC-Na solution was 0.05 mL per 10g of body weight and so that the dose of the test substances was thevalue shown in Table 1.

2. Administration Test

Forty two hairless mice Hos:HR1 (male, 5-week old) were prepared.Through the 1-week acclimation period and the test period, the mice werefreely fed a reference diet (product name: CRF-1, manufactured byOriental Yeast Co., Ltd.) and water. The insolation condition was set today and night every 12 hours. After the acclimation period, grouping of6 mice/group was performed so that the body weight between groups washomogenous.

Continuous and forced intragastric administration of the abovecomposition was performed to the mice once a day for 28 days using astomach tube. The reference diet and 0.05 mL per 10 g of body weight ofa 0.5% CMC-Na solution were administered to the control group.

TABLE 6 Test substance Dose of test substance Control — — ComparativeMenaquinone-7 10 mg/kg of body weight Example 1 Comparative Collagentripeptide 80 mg/kg of body weight Example 2 Comparative Soyasapogenol50 mg/kg of body weight Example 3 Example 1 Menaquinone-7 10 mg/kg ofbody weight Collagen hydrolysate 80 mg/kg of body weight Example 2Menaquinone-7 10 mg/kg of body weight Soyasapogenol 50 mg/kg of bodyweight Example 3 Collagen hydrolysate 80 mg/kg of body weightSoyasapogenol 50 mg/kg of body weight

3. Evaluation of Skin Function Improving Agent (1) Transdermal MoistureLoss-Inhibiting Function

By measuring TEWL values, the transdermal moisture loss-inhibitingfunction (i.e., skin barrier function) of the composition (skin functionimproving agent) was evaluated. In measurement of TEWL, a commercialtewameter (product name: TM300, manufactured by Integral Corporation)was used. The back of the mice was used for the measurement site.Measurement was performed on the day before test substanceadministration and days 14 and 28 after administration.

FIGS. 1A to 1C show the values in which the transepidermal water loss onthe day before test substance administration is subtracted from thetransepidermal water loss on day 28 after test substance administration.A significance test of measurement results was performed by Tukey'smultiple comparison test. In the figures, * and ** represent the case inwhich there is a significant difference with a significance level (P) ofP<0.05 and P<0.01, respectively.

FIG. 1B shows that decreases in the transepidermal water loss weresignificantly inhibited compared with that in the control group inExample 2 (menaquinone-7 and soyasapogenol) (P<0.05). Also in Example 1(menaquinone-7 and collagen hydrolysate) in FIG. 1A and Example 3(collagen hydrolysate and soyasapogenol) in FIG. 1C, a tendency toinhibit the transepidermal water loss was observed. These findingsreveal that a skin function improving agent of the present invention,especially a skin function improving agent containing menaquinone-7 andsoyasapogenol, is effective for inhibiting moisture loss in thesebaceous membrane.

(2) Stratum Corneum Water-Retaining Function

The keratin usually contains 20% to 30% of water. It is considered thata lower amount of moisture in the keratin is associated with decreasesin water in the stratum corneum or a natural moisturizing factor (NMF)involved in water retention, resulting in dryness of the skin. Bymeasuring the moisture in the keratin, the stratum corneumwater-retaining function (i.e., skin moisture-retaining function) of askin function improving agent can be evaluated.

In measurement of the moisture in the keratin, a commercial corneometer(product name: CM825, manufactured by Integral Corporation) was used.The back of the mice was used for the measurement site. Measurement wasperformed on the day before test substance administration and days 14and 28 after administration.

FIG. 2A to C show the values in which the reference of the moisture inthe keratin on the day before test substance administration issubtracted from the moisture in the keratin on day 28 after testsubstance administration. A significance test of measurement values wasperformed by Tukey's multiple comparison test. In the figures, * and **represent the case in which there is a significant difference with asignificance level (P) of P<0.05 and P<0.01, respectively.

FIG. 2A shows that the use of menaquinone-7 or collagen hydrolysatealone does not exert the keratin water-retaining function. However, asin the present invention, combination of menaquinone-7 and collagenhydrolysate exerts the keratin water-retaining function. This findingreveals that a skin function improving agent of the present inventioncontaining menaquinone-7 and collagen hydrolysate is effective forretaining moisture in the stratum corneum.

FIG. 2B shows that the use of menaquinone-7 alone does not exert thestratum corneum water-retaining function, but the use of soyasapogenolalone exerts the function. As in the present invention, even combinationof menaquinone-7 and soyasapogenol exerts the keratin water-retainingfunction.

What is claimed:
 1. A composition comprising sapogenol and collagenhydrolysate.
 2. The composition according to claim 1, wherein thesapogenol is derived from soybean.
 3. The composition according to claim1, wherein a content of peptide having a molecular weight from 200 toless than 3,000 in the collagen hydrolysate is not less than 40% bymass.
 4. A skin function improving agent comprising the compositionaccording to claim 1 as an active ingredient.
 5. The skin functionimproving agent according to claim 4, wherein the skin function is atransdermal moisture loss-inhibiting function.
 6. The skin functionimproving agent according to claim 4, wherein the skin function is afunction of retaining the moisture in the stratum corneum.